A U.S. grand jury has formally charged four men with planning to attack John F. Kennedy International Airport in New York by blowing up fuel tanks and pipelines.

The indictment was filed in U.S. federal court in Brooklyn, New York, on Friday. It charges Guyanese-born American Russell Defreitas, two other Guyanese nationals Abdul Kadir and Abdel Nur and a Trinidadian Kareem Ibrahim with conspiring to cause death, serious bodily injury and extensive destruction.

Defreitas is to be arraigned on July 11. The former airport employee and the other suspects were arrested earlier this month in the United States and in Trinidad and Tobago.

Authorities say the plot never went beyond the planning stage.

Federal law enforcement officials had been tracking the plot through an informant since January 2006. Authorities say one of the suspects bragged to the informant that he believed the airport attack would be worse than the attacks in the United States on September 11, 2001.